# Send emails with .NET

## Prerequisites

Before you start, you'll need:

- A Resend [API key](/guides/get-started-create-an-api-key)
- A [verified domain](/guides/get-started-add-a-domain)

Prefer watching a video? Check out our video walkthrough below.

[YouTube video player](https://www.youtube.com/watch?v=HvFURxq1tgQ)

## Guide

:::::steps
::::step{title="Install"}
:::code-group
```bash dotnet CLI theme={"theme":{"light":"github-light","dark":"vesper"}}
dotnet add package Resend
```

```bash Visual Studio (Package Manager Console) theme={"theme":{"light":"github-light","dark":"vesper"}}
PM> Install-Package Resend
```
:::
::::

:::step{title="Send emails using HTML"}
In the startup of your application, configure the DI container as follows:

```csharp theme={"theme":{"light":"github-light","dark":"vesper"}}
using Resend;

builder.Services.AddOptions();
builder.Services.AddHttpClient<ResendClient>();
builder.Services.Configure<ResendClientOptions>( o =>
{
    o.ApiToken = Environment.GetEnvironmentVariable( "RESEND_APITOKEN" )!;
} );
builder.Services.AddTransient<IResend, ResendClient>();
```

Send an email using the injected `IResend` instance:

```csharp theme={"theme":{"light":"github-light","dark":"vesper"}}
using Resend;

public class FeatureImplementation
{
    private readonly IResend _resend;


    public FeatureImplementation( IResend resend )
    {
        _resend = resend;
    }


    public Task Execute()
    {
        var message = new EmailMessage();
        message.From = "Acme <onboarding@resend.dev>";
        message.To.Add( "delivered@resend.dev" );
        message.Subject = "hello world";
        message.HtmlBody = "<strong>it works!</strong>";

        await _resend.EmailSendAsync( message );
    }
}
```
:::
:::::

## Examples

::::card-grid
:::card{title="Basic Send" href="https://github.com/resend/resend-examples/blob/main/dotnet-resend-examples/Examples/BasicSend.cs" icon="arrow-up-right-from-square"}
Basic email sending
:::

:::card{title="Attachments" href="https://github.com/resend/resend-examples/blob/main/dotnet-resend-examples/Examples/WithAttachments.cs" icon="arrow-up-right-from-square"}
Send emails with file attachments
:::

:::card{title="Templates" href="https://github.com/resend/resend-examples/blob/main/dotnet-resend-examples/Examples/WithTemplate.cs" icon="arrow-up-right-from-square"}
Send emails using Resend hosted templates
:::

:::card{title="Scheduling" href="https://github.com/resend/resend-examples/blob/main/dotnet-resend-examples/Examples/ScheduledSend.cs" icon="arrow-up-right-from-square"}
Schedule emails for future delivery
:::

:::card{title="Audiences" href="https://github.com/resend/resend-examples/blob/main/dotnet-resend-examples/Examples/Audiences.cs" icon="arrow-up-right-from-square"}
Manage contacts and audiences
:::

:::card{title="Domains" href="https://github.com/resend/resend-examples/blob/main/dotnet-resend-examples/Examples/Domains.cs" icon="arrow-up-right-from-square"}
Create and manage sending domains
:::

:::card{title="Inbound Webhooks" href="https://github.com/resend/resend-examples/blob/main/dotnet-resend-examples/Examples/Inbound.cs" icon="arrow-up-right-from-square"}
Receive and process inbound emails
:::

:::card{title="Double Opt-in" href="https://github.com/resend/resend-examples/blob/main/dotnet-resend-examples/Examples/DoubleOptinSubscribe.cs" icon="arrow-up-right-from-square"}
Double opt-in subscription flow
:::

:::card{title="Minimal API App" href="https://github.com/resend/resend-examples/tree/main/dotnet-resend-examples/MinimalApiApp" icon="arrow-up-right-from-square"}
ASP.NET Minimal API application
:::

:::card{title="MVC App" href="https://github.com/resend/resend-examples/tree/main/dotnet-resend-examples/MvcApp" icon="arrow-up-right-from-square"}
ASP.NET MVC application
:::
::::

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